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标准地铁列车供风系统技术参数统型分析 被引量:1
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作者 涂贵军 孟繁辉 +2 位作者 袁世琳 吴学瑞 李龙 《铁道车辆》 2023年第3期69-74,共6页
基于标准地铁车辆条件,对供风系统的总风工作压力和初充风时间两个关键顶层参数的统型开展了分析。通过仿真计算,对比了不同总风工作压力下列车制动次数的差异,分析了车辆编组、城市海拔高度等因素对列车初充风时间的影响。结果表明,总... 基于标准地铁车辆条件,对供风系统的总风工作压力和初充风时间两个关键顶层参数的统型开展了分析。通过仿真计算,对比了不同总风工作压力下列车制动次数的差异,分析了车辆编组、城市海拔高度等因素对列车初充风时间的影响。结果表明,总风工作压力提高将有助于增加制动允许次数,当其从750~900 kPa提高到800~950 kPa后,紧急制动次数增加1次,最大常用制动次数增加2次;海拔高度的增加、系统空压机停机压力的提高和空压机标称排量的增大均会导致列车初充风时间延长,而车辆编组的增加也会导致初充风时间延长,初充风时间顶层参数的统型不可一概而论,应区分不同海拔高度、不同车辆编组因素,文章对标准地铁总风工作压力及初充风时间指标统型提出了建议。 展开更多
关键词 地铁列车 供风系 总风工作压力 初充风时间 统型分析
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Application of neural network merging model in dam deformation analysis 被引量:5
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作者 张帆 胡伍生 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期441-444,共4页
In order to improve the prediction accuracy and test the generalization ability of the dam deformation analysis model, the back-propagation(BP) neural network model for dam deformation analysis is studied, and the m... In order to improve the prediction accuracy and test the generalization ability of the dam deformation analysis model, the back-propagation(BP) neural network model for dam deformation analysis is studied, and the merging model is built based on the neural network BP algorithm and the traditional statistical model. The three models mentioned above are calculated and analyzed according to the long-term deformation observation data in Chencun Dam. The analytical results show that the average prediction accuracies of the statistical model and the BP neural network model are ~ 0.477 and +- 0.390 mm, respectively, while the prediction accuracy of the merging model is ~0. 318 mm, which is improved by 33% and 18% compared to the other two models, respectively. And the merging model has a better generalization ability and broad applicability. 展开更多
关键词 dam deformation analysis neural network statistical model merging model
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Reliability Analysis of a Mixed Redundant Model in C 3I System 被引量:1
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作者 徐勇 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期324-330,共7页
Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute s... Aim To define a mixed redundant model(MRM), improving the reliability of C 3I system. Methods The model combined the technology characters of two? unit system with one warm stand by unit and function substitute system. The reliability and availability equations of MRM were deduced. Results and Conclusion Compared with several other reliability models, it has obvious effect upon improving the system reliability. The effect? cost rate is very high among these models. The model can be used in reliability design, evaluation and check of C 3I system. Only a little attached cost is needed to improve C 3I system reliability effectively. 展开更多
关键词 C 3I system reliability analysis mixed redundant model
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Expression and Phylogenetic Analysis of Pea Actin Isoforms 被引量:5
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作者 江元清 赵武玲 《Acta Botanica Sinica》 CSCD 2002年第12期1456-1461,共6页
Pea ( Pisum sativum Linn.) actin gene family contains at least three isoforms (PEAcⅠ, PEAcⅡand PEAcⅢ), and the DNA sequence of these isoforms show high similarity in the coding regions and significant divergence... Pea ( Pisum sativum Linn.) actin gene family contains at least three isoforms (PEAcⅠ, PEAcⅡand PEAcⅢ), and the DNA sequence of these isoforms show high similarity in the coding regions and significant divergence in the untranslated regions. RT_PCR and Southern blotting using 3′_untranslated region (3′_UTR) as specific probe revealed that pea isoactin genes were expressed in roots, stems, leaves, tendrils, pollen and juvenile siliques, but displayed different patterns of transcript accumulation. Two_fold serial dilution electrophoresis showed PEAcⅠ mRNA preferentially accumulated in rapidly developing tissues: it peaked in seven days' stem; remained at a rather high level in leaves within a month but decreased significantly later; varied a little in tendrils and reached a median and a very low level respectively in juvenile siliques and in pollen. PEAcⅡ displayed somewhat similar expression pattern to PEAcⅠ. The observed differences in sequences and transcript accumulation patterns suggest that the individual pea actin genes may differ in their transcriptional regulation and cellular function. Phylogenetic tree of actins showed that pea actin isoforms are as diverged from each other as they are from other plant actins, and pea actins might have originated from a common ancestor before the divergence of the dicot and monocot plants. 展开更多
关键词 ACTIN 3′_untranslated region (3′_UTR) differential expression molecular evolution pea ( Pisum sativum )
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Evaluation model for freeway incident management system 被引量:2
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作者 何锭 倪富健 杨顺新 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期126-131,共6页
In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evalu... In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evaluation index. As a result, 81 indices and the hierarchical structures of the index such as the object layer, the sub-object layer, the criterion layer and the index layer are determined. Then, based on the fuzzy characteristics of each index layer, the analytical hierarchy process(AHP)and the fuzzy comprehensive evaluation are applied to generate the weight and the satisfaction of the index and the criterion layers. When analyzing the relationship between the sub-object layer and the object layer, it is easy to find that the number of sub-objects is too large and sub-objects are significantly redundant. The partial least square (PLS) is proposed to solve the problems. Finally, an application example, whose result has already been accepted and employed as the indication of a new project in improving incident management, is introduced and the result verifies the feasibility and efficiency of the model. 展开更多
关键词 freeway incident management system evaluation model analytical hierarchical process fuzzy comprehensive evaluations partial least square
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HIERARCHIC GREY QUASI-PREFERRED ANALYSIS MODEL AND ITS APPLICATION
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作者 李炳军 刘思峰 任盈盈 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第1期78-83,共6页
The grey quasi-preferred analysis (GQPA) is one of important methods for realizing system analysis to conquer the limitations of the existing GQPA model, without any considerations to the difference of the different b... The grey quasi-preferred analysis (GQPA) is one of important methods for realizing system analysis to conquer the limitations of the existing GQPA model, without any considerations to the difference of the different behavioral factor′s importance. It could not be used to analyze the complex system with multi-hierarchy correlation factors, the weighted synthetic method for calculating abstract incidence degrees between the system beha-vioral characteristics and correlative factors in different hierarchies is given out,and the hierarchic grey quasi-preferred analysis (HGQPA) model is established. The effectiveness of the HGQPA model is tested by the scientific-technical system of Jiangsu Province. The depth and the range of the application of GQPA are developed, and the HGQPA model is regarded as a new approach to systemically analyze the complex systems with multi-hierarchy correlation factors. 展开更多
关键词 multi-hierarchy quasi-preferred analysis MODEL grey system
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Prediction on hot deformation behavior of spray-formed 7055 aluminum alloy via phenomenological models 被引量:7
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作者 Xiang-dong WANG Qing-lin PAN +3 位作者 Shang-wu XIONG Li-li LIU Yuan-wei SUN Wei-yi WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第8期1484-1494,共11页
Hot compression tests in the temperature range of 340-450 ℃ and strain rate range of 0.001-1 s^-1 of spray-formed 7055 aluminum alloy were carried out to study its hot deformation behavior. Three phenomenological mod... Hot compression tests in the temperature range of 340-450 ℃ and strain rate range of 0.001-1 s^-1 of spray-formed 7055 aluminum alloy were carried out to study its hot deformation behavior. Three phenomenological models including Johnson-Cook, modified Fields-Backofen and Arrhenius-type were introduced to predict the flow stresses during the compression process. And then, a comparative predictability of the phenomenological models was estimated in terms of the relative errors, correlation coefficient(R), and average absolute relative error(AARE). The results indicate that Johnson-Cook model and modified Fields-Backofen model cannot well predict the hot deformation behavior due to the large deviation in the process of line regression fitting. Arrhenius-type model obtains the best fit through combining the effect of strain rate and temperature. 展开更多
关键词 spray-formed 7055 aluminum alloy hot deformation behavior phenomenological models statistical analyses
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Rocky Desertification Risk Zone Delineation in Karst Plateau Area:A Case Study in Puding County,Guizhou Province 被引量:15
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作者 ZHANG Panpan HU Yuanman +3 位作者 XIAO Duning LI Xiuzhen YIN Jie HE Hong S 《Chinese Geographical Science》 SCIE CSCD 2010年第1期84-90,共7页
Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management a... Karst rocky desertification is a geo-ecological problem in Southwest China. The rocky desertification risk zone delineation could be used as a guide for the regional and hierarchical rocky desertification management and prevention. We chose the middle and lower reaches of the Houzhai underground basin on the karst plateau in Puding County, Guizhou Province, China as the study area and selected land use type, elevation, slope, aspect, lithology and settlement buffer as the main driving factors of the rocky desertification. The potential risk of rocky desertification was quantifed with the factor-weights union method and statistical analysis method. Five grades of rocky desertification risk were delineated based on Geographic Information System. The extremely low, low, moderate, high and extremely high rocky desertification risk zones accounted for 5.01%, 44.17%, 33.92%, 15.59% and 1.30%, respectively. As a whole, the rocky desertification risk level was moderate because the area of low and moderate rocky desertification risk zones occupied 78.09% of the study area. However, more than half of the area (about 50.81%) was predicted to have moderate rocky desertification risk and above, indicating that the study area was subject to rocky desertification. Rocky desertification risk was higher in the southeast and lower in the northwest of the study area. Distinct differences in the distribution of rocky desertification risk zones corresponding to different factors have been found. 展开更多
关键词 rocky desertification rocky desertification risk zone karst plateau Guizhou Province
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Evaluation and optimization of secondary water supply system renovation 被引量:5
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作者 TIAN Yi-mei SI Yan-jie +1 位作者 LI Hong WU Mi-fang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第9期1488-1494,共7页
Due to pollution in second water supply system (SWSS),nine renovation alternative plans were proposed and com-prehensive evaluations of different plan based on Analytical Hierarchy Process (AHP) were presented in this... Due to pollution in second water supply system (SWSS),nine renovation alternative plans were proposed and com-prehensive evaluations of different plan based on Analytical Hierarchy Process (AHP) were presented in this paper. Comparisons of advantages and disadvantages among the plans of SWSS renovations provided solid foundation for selecting the most appro-priate plan for engineering projects. In addition,a mathematical model of the optimal combination of renovation plans has been set up and software Lingo was used to solve the model. As a case study,the paper analyzed 15 buildings in Tianjin City. After simulation of the SWSS renovation system,an optimal scheme was obtained,the result of which indicates that 10 out of those 15 buildings need be renovated in priority. The renovation plans selected for each building are the ones ranked higher in the com-prehensive analysis. The analysis revealed that the optimal scheme,compared with two other randomly calculated ones,increased the percentage of service population by 19.6% and 13.6% respectively,which significantly improved social and economical benefits. 展开更多
关键词 Secondary water supply system (SWSS) Renovation plan Analytical Hierarchy Process (AHP) Hierarchical model OPTIMIZATION
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Time between failures model and failure analysis of CNC system 被引量:4
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作者 张海波 贾亚洲 周广文 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期197-201,共5页
To provide basis for the reliability improvement design of CNC system, the failure data of a type of CNC system in one year are collected under field conditions in workshops. The distribution model parameters of time ... To provide basis for the reliability improvement design of CNC system, the failure data of a type of CNC system in one year are collected under field conditions in workshops. The distribution model parameters of time between failures are estimated by least square method and hypothesis testing is done by d-test method. It is proved that the time between failures of the CNC system follows Weibull distribution and the system has entered into the wear-out failure period. The failure positions and failure causes are analyzed further to indicate the weak subsystems of the CNC system. It can be found that servo unit, electrical system, detecting unit and power supply are principal failure positions and the main failure cause is breakage of components. The corresponding improvement measures are put forward. The paper provides a reference to reliability design and analysis of CNC system for the manufacturer and has great guidance to using and maintaining CNC system for the user. 展开更多
关键词 CNC system failure analysis RELIABILITY Weibull distribution
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Topographic Correction-Based Retrieval of Leaf Area Index in Mountain Areas 被引量:6
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作者 CHEN Wei CAO Chunxiang 《Journal of Mountain Science》 SCIE CSCD 2012年第2期166-174,共9页
Leaf Area Index(LAI)is a key parameter in vegetation analysis and management,especially for mountain areas.The accurate retrieval of LAI based on remote sensing data is very necessary.In a study at the Dayekou forest ... Leaf Area Index(LAI)is a key parameter in vegetation analysis and management,especially for mountain areas.The accurate retrieval of LAI based on remote sensing data is very necessary.In a study at the Dayekou forest center in Heihe watershed of Gansu Province,we determined the LAI based on topographic corrections of a SPOT-5.The large variation in the mountain terrain required preprocessing of the SPOT-5 image,except when orthorectification, radiation calibration and atmospheric correction were used.These required acquisition of surface reflectance and several vegetation indexes and linkage to field measured LAI values.Statistical regression models were used to link LAI and vegetation indexes.The quadratic polynomial model between LAI and SAVI (L=0.35)was determined as the optimal model considering the R and R2 value.A second group of LAI data were reserved to validate the retrieval result.The model was applied to create a distribution map of LAI in the area.Comparison with an uncorrected SPOT-5 image showed that topographic correction is necessary for determination of LAI in mountain areas. 展开更多
关键词 SPOT-5 image Vegetation Index Leaf Area Index Topographic correction Mountain areas
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Application of artificial neural networks and multivariate statistics to estimate UCS using textural characteristics 被引量:15
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作者 Amin Manouchehrian Mostafa Sharifzadeh Rasoul Hamidzadeh Moghadam 《International Journal of Mining Science and Technology》 SCIE EI 2012年第2期229-236,共8页
Before any rock engineering project,mechanical parameters of rocks such as uniaxial compressive strength and young modulus of intact rock get measured using laboratory or in-situ tests,but in some situations preparing... Before any rock engineering project,mechanical parameters of rocks such as uniaxial compressive strength and young modulus of intact rock get measured using laboratory or in-situ tests,but in some situations preparing the required specimens is impossible.By this time,several models have been established to evaluate UCS and E from rock substantial properties.Artificial neural networks are powerful tools which are employed to establish predictive models and results have shown the priority of this technique compared to classic statistical techniques.In this paper,ANN and multivariate statistical models considering rock textural characteristics have been established to estimate UCS of rock and to validate the responses of the established models,they were compared with laboratory results.For this purpose a data set for 44 samples of sandstone was prepared and for each sample some textural characteristics such as void,mineral content and grain size as well as UCS were determined.To select the best predictors as inputs of the UCS models,this data set was subjected to statistical analyses comprising basic descriptive statistics,bivariate correlation,curve fitting and principal component analyses.Results of such analyses have shown that void,ferroan calcitic cement,argillaceous cement and mica percentage have the most effect on USC.Two predictive models for UCS were developed using these variables by ANN and linear multivariate regression.Results have shown that by using simple textural characteristics such as mineral content,cement type and void,strength of studied sandstone can be estimated with acceptable accuracy.ANN and multivariate statistical UCS models,revealed responses with 0.87 and 0.76 regressions,respectively which proves higher potential of ANN model for predicting UCS compared to classic statistical models. 展开更多
关键词 Textural characteristicsUniaxial compressive strengthPredictive modelsArtificial neural networksMultivariate statistics
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Electromechanical dynamics analysis and simulation on rollforming equipment with both sides variable cross-section 被引量:4
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作者 闫军 Li Qiang Zhou Zhixia 《High Technology Letters》 EI CAS 2016年第1期75-81,共7页
Electromechanical dynamics analysis and simulation on a rollforming equipment with both sides variable cross-section are discussed in this study.The system includes mechanical parts and electromagnetism parts,and it i... Electromechanical dynamics analysis and simulation on a rollforming equipment with both sides variable cross-section are discussed in this study.The system includes mechanical parts and electromagnetism parts,and it is a strongly coupled electromechanical system.Based on a virtual work principle and given power,generalized forces of this system are obtained.By using Lagrange-Maxwell equations,a model of electromechanical dynamics is established.Differential equations of two-phase winding on d-q axis are obtained by Park transformation,which comes from three-phase winding equations on the A-B-C axis.This system is solved with the 4th order Runge-Kutta's method,and discrete solutions of all variables are obtained.Finally,by using Matlab language,the system is simulated.The results show that the proposed method works very well. 展开更多
关键词 electromechanical dynamics electromechanical coupling system virtual work principle Runge-kutta' s method
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Performance analysis model for real-time Ethernet-based computer numerical control system 被引量:2
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作者 万加富 李迪 +1 位作者 涂钰青 张春华 《Journal of Central South University》 SCIE EI CAS 2011年第5期1545-1553,共9页
In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign met... In order to optimize the embedded system implementation for Ethernet-based computer numerical control (CNC) system, it is very necessary to establish the performance analysis model and further adopt the codesign method from the control, communication and computing perspectives. On the basis of analyzing real-time Ethemet, system architecture, time characteristic parameters of control-loop ere, a performance analysis model for real-time Ethemet-based CNC system was proposed, which is able to include the timing effects caused by the implementation platform in the simulation. The key for establishing the model is accomplished by designing the error analysis module and the controller nodes. Under the restraint of CPU resource and communication bandwidth, the experiment with a case study was conducted, and the results show that if the deadline miss ratio of data packets is 0.2%, then the percentage error is 1.105%. The proposed model can be used at several stages of CNC system development. 展开更多
关键词 computer numerical control (CNC) system real-time Ethemet time characteristic parameters performance analysis model manufacturing accuracy
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The expression and clinical significance of KAI1 and CD44v6 protein in human osteosarcoma
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作者 Weihua Hu Anmin Chen Fengjing Guo Feng Li 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第4期232-236,共5页
Objective:To investigate the expressions of KAI1 and CD44v6 in human osteosarcoma and the relationship between expressions of them and their clinic pathological features and prognosis.Methods:The expressions of KAI1 a... Objective:To investigate the expressions of KAI1 and CD44v6 in human osteosarcoma and the relationship between expressions of them and their clinic pathological features and prognosis.Methods:The expressions of KAI1 and CD44v6 in 87 samples with osteosarcoma were detected by S-P immunohistochemistry.Results:Expression of KAI1 had correlation with metastasis of osteosarcoma,and was strongly associated with differentiation of tumor cells.The expression of CD44v6 in osteosarcoma had correlation with metastasis.There was no difference between the expression of KAI1 and CD44v6.Cox model analysis showed that the prognostic factors were KAI1 expression,metastasis and Enneking surgical staging system.Conclusion:The abnormal expression of KAI1 and CD44v6 participate metastasis of osteosarcoma,KAI1 expression,metastasis and Enneking surgical staging system can be used to independently predict the prognosis of osteo-sarcoma patients. 展开更多
关键词 KAI1 CD44V6 OSTEOSARCOMA METASTASIS
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Statistical Analysis on Depth Distribution Model of Earthquake Hypocenters
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作者 Xu Guangyin, Gao Mengtan, Yu Yanxiang and Wang JianInstitute of Geophysics, CSB, Beijing 100081, China 《Earthquake Research in China》 2002年第2期113-119,共7页
In order to improve reliability of probabilistic seismic hazard analysis, shallow earthquake (depth <70 km) data, recorded with orientation precision grades 1 and 2 by modern instrument and containing depth informa... In order to improve reliability of probabilistic seismic hazard analysis, shallow earthquake (depth <70 km) data, recorded with orientation precision grades 1 and 2 by modern instrument and containing depth information after 1970, are selected as statistical samples, meanwhile, North China seismic region, Central China seismic region, South China seismic region, Xinjiang seismic region and Qinghai-Xizang Plateau seismic region are chosen as statistical units to study the depth distribution characteristics of shallow earthquakes. Considering the differences of depth distribution characteristics of earthquakes with different magnitudes, the following magnitude intervals are adopted to analyze earthquakes with different magnitude scales, respectively: M S=2.0~2.9, M S=3.0~3.9, M S=4.0~4.9, M S=5.0~5.9 and M S=6.0~6.9. The results show that hypocenter depths are normally distributed by and large around the mean depth of the corresponding seismic region. The probabilistic distribution curves of earthquake depth in West China are wider than those in East China. The probabilistic distribution deviation, σ, of West China is greater than those of East China, that is, earthquakes in West China have a wider range in terms of depth. There is also a tendency that the absolute value of mean hypocenter depth increases with the magnitude by and large. 展开更多
关键词 Shallow earthquake Hypocenter depth Distribution model Seismic region Magnitude interval
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Survey of cyanomyovirus abundance in Shantou coastal waters by g20 被引量:1
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作者 李传标 丁俊 +4 位作者 周立镇 张昭 李升康 刘文华 温小波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期604-615,共12页
To understand the genetic diversity and population changes in cyanophages in the coastal waters of Shantou, northeast South China Sea, we used the capsid assembly protein gene g20 as a marker of the abundance and phyl... To understand the genetic diversity and population changes in cyanophages in the coastal waters of Shantou, northeast South China Sea, we used the capsid assembly protein gene g20 as a marker of the abundance and phylogeny of natural cyanomyovirus communities. The abundance of total viruses, heterotrophic bacteria, and picophytoplankton in the coastal waters was monitored with flow cytometry. Hydrological parameters (NO3^-, NO2^-, NH3, soluble reactive phosphorus, total dissolved nitrogen, total dissolved phosphorus, dissolved oxygen, chemical oxygen demand, temperature, salinity, and chlorophyll a concentration) and microbial abundance (total viruses, total bacteria, Prochlorococcus, Synechococcus, and eukaryotes) were measured in the upper and lower layers at four sampling sites in the research area. In the direct viral counts, cyanomyoviruses accounted for 1.92% to 〉10% of the total viral community. A phylogenetic analysis showed that the g20 sequences in the Shantou coastal waters were very diverse, distributed in eight distinct operational taxonomic units, including the newly formed Cluster W. The g20 gene copies inferred from real time PCR assay indicated that cyanomyovimses were correlated significantly with the heterotrophic bacteria numbers and the nitrate and chlorophyll a concentrations. These results suggest that cyanomyoviruses are ubiquitous and are an abundant component of the virioplankton in Shantou coastal waters. 展开更多
关键词 cyanomyovims G20 Shantou coastal water
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Evaluation of Energy Use and Environmental Efficiency in China's A statistical analysis by province based on the SBM model
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作者 涂正革 刘磊珂 《China Economist》 2011年第4期54-69,共16页
The world today is .faced with the critical challenge of developing industries .for both high technological efficiency and possibly less impact on resources and the environment. This paper employs the Slacks-based mea... The world today is .faced with the critical challenge of developing industries .for both high technological efficiency and possibly less impact on resources and the environment. This paper employs the Slacks-based measure (SBM) to conduct an empirical analysis of China's industrial environmental efficiency between 1998 and 2008. We.found a slight decline in SBM nationwide due to the combined effects of resource^environmental constraint as well as technological progress. From a static perspective, there is a clear disparity in coordination among regions, particularly between western regions and eastern coastal regions. From a dynamic perspective, there is limited change in the coordination of industries with natural resources and the environment in coastal and central regions, but a marked decline in the northeast and western regions. This contrast can be traced to the .following reasons: the capital-intensive structure of the economy and the high proportion of large industrial enterprises that restrict the improvement of SBM environmental efficiency. Higher living standards, indigenous innovation, acquisition of new technologies, and foreign direct investment will be conducive to industries'synchronous development with natural resources and the environment. 展开更多
关键词 data envelope analysi SBM environmental efficiency resource-efficient andenvironment-friendly society
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Analysis of certain differential equation models in the economic system
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作者 Xingcong Mao 《International Journal of Technology Management》 2013年第4期86-88,共3页
The basic contradiction of socialist society is still a contradiction between the relations of production and productivity, the superstructure and the economic base. This contradiction is concentrated in the productio... The basic contradiction of socialist society is still a contradiction between the relations of production and productivity, the superstructure and the economic base. This contradiction is concentrated in the production relations and a series of interconnected links and aspects in the superstructure that don't match the development of the productivity, these links and they are concentrated in the economic system. Therefore, reforming the economic system is to reform the production relations and a series of interconnected links and aspects in the superstructure that don't match the development of the productivity under the premise of adhering to the basic system of socialism. This re^brm is a self-improvement and development of the socialist system in order to promote the development of the socialist productive forces and the development of socialist modernization greatly. 展开更多
关键词 equation models economic system reform.
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Convergence Study of Chinese Carbon Intensity
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作者 Bo WANG 《International Journal of Technology Management》 2014年第11期72-75,共4页
This paper establishes the theoretical hypothesis of carbon intensity convergence, and through statistics to analyze and describe the whole country and the eastern and western regions with the use of mixed regression ... This paper establishes the theoretical hypothesis of carbon intensity convergence, and through statistics to analyze and describe the whole country and the eastern and western regions with the use of mixed regression model and fixed effects regression method, and test σ -convergence, absolute convergence and conditional convergence in order to have an empirical study on carbon convergence hypothesis. 展开更多
关键词 carbon emissions INTENSITY CONVERGENCE Economic Growth
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